No Duck Mo (“NDM”) - Part 2, Height Adjustment

In my mind’s eye I was looking at a lift bridge, hinged at one end and free to lift at the other. The hinge side would sit atop a height-adjustable tower as would the open-close side. These towers would need to be sufficiently far apart to allow easy passage of portly adults. The height adjustment characteristic had to be solved first because without that the NDM would be useless.

I used four ball-bearing drawer slides that are commonly found in office furniture such as filing cabinets and desk drawers. These operate very smoothly, have no lateral play, are available in several lengths and are quite easy to find at home centres (I purchased mine from The Home Depot).

one vertical tower showing the drawer slides partially extended
the vertical towers; colour coding is to facilitate setup and packing so I know which piece goes where
Two drawer slides are mounted on either side of each of the two towers. The lower portion of each tower consists of two 2x3’s glued together to make a nominal 4x3 (while dimensional lumber is sold in dimensions that are up to 25% in error – a 2x3 actually measures 1.5x2.5 inches, I shall refer to the nominal amounts when referring to dimensional lumber). These fit snugly into a pocket affixed to the base and are held in place by a 5-inch long bolt which passes through the pocket and the bottom of each tower (no nut is needed to keep these bolts in place). The bolts are also used to fasten the top of the “coffin” used to transport the NDM. 

The vertical towers inserted into the base; additional information about the base will be contained in Part 3
The top movable  portion of each tower also consists of two 2x3’s glued together to make a nominal 4x3. The drawer slides are attached to the sides of the nominal 4x3 pieces, allowing for the free vertical adjustment of each tower.

One large closed hook is fastened on the upper portion of each tower, to which is attached one end of a large turnbuckle. The lower end of the turnbuckle is fastened to the lower portion of the tower. The turnbuckles I purchased have a lock nut at each end, helpful but not mandatory. I purchased these from Princess Auto.

There are additional, smaller turnbuckles that pass between two hooks mounted to the end of the base and to the tower. The purpose of these turnbuckles is to make fine adjustments to the inward-outward position of the towers so that the bridge is positioned with perfect clearance from end to end – too sloppy and there will be a “pothole” in the track, too snug and the bridge won’t close all the way. These turnbuckles are adjusted as part of the final setup.

The lower end of the turnbuckle is positioned in an open hook located at the base of each tower – the turnbuckle needs to be able to be removed from the bottom hook for transporting.

To be continued...

No Duck Mo (“NDM”) - Part 1, Need & Attributes

This is the first of a multi-part series of posts on the design, construction and operation of a Free-mo module which I call the No Duck Mo, so named because it avoids having to duck under modules to transit from one side of a Free-mo layout to the other (the "No Duck") and because it is Free-mo module (the "Mo"). A simplified version could be built in a non-Free-mo setting, as for a fixed basement layout. 

The Need

If you have read my blog entries describing Big Valley Free-mo events and if you study the layout maps carefully you will soon realize that it not possible for an adult to freely walk through the layout, without having to either crawl underneath where there are wires, etc. or detour up to the length of an ice hockey rink.

To transit from one side of the layout to the other, participants must traditionally make use of “duck-under”, modules which have a somewhat shallower profile than other modules to allow for participants to physically duck under the layout. While this is not particularly difficult for the younger participants, once a person reaches age 60 this can take a toll on the back and legs over the course of several days.

This is exacerbated by the fact that the top of the layout is 42 inches from the floor (floor to rail head) which is not the Free-mo standard height of 50 inches. However, this is a height better suited to train shows and has been adopted by the Calgary; Chilliwack, BC; Spokane, WA; and Regina groups, among others. The Winnipeg group have adopted 40 inches.

Big Valley 2018; traditional duck under on right, No Duck Mo (open) at left

Big Valley 2018; traditional duck under on right, No Duck Mo (open) at left

Must-have Attributes

Following my first Big Valley experience in 2017 I had an 8-hour drive home to Regina. As I made much use of the seat heater to ease my aching back, I was determined to come up with a better alternative. Any design would have to include a means of breaking the continuity of the rails while at the same time conforming to all the following characteristics:
  • Easy to use by participants 
  • Portable 
  • Height adjustable from the official Free-mo height of 50 inches from floor to rail head to Winnipeg's 40 inches 
  • Robust to operate without fail 
  • Safe for both people and expensive rolling stock – must avoid trains falling through the gap
  • Electrically compatible with Free-mo (allow current to flow uninterrupted to and from adjacent modules, even when rail continuity is broken) 
Subsequent blog entries will outline the design, construction and operation of my NDM prototype.

This would be an appropriate point to outline my approach to design. Not being an engineer or a drafts person (therefore lacking training in the science of forces, levers, torque, etc.) and not being particularly artistic (therefore not very good at sketching three-dimensional objects) and disliking paralysis by analysis, my approach is generally to toss a few ideas around in my head, look through my parts bin and take a stroll through hardware or automotive supply stores to see what I can purpose and often re purpose for my needs. After a short period of conceptual thinking I like to get started. As the late great Walt Disney’s once said, “The way to get started is to quit talking and begin doing.”

Generally, any sketches found in my blogs will have been made after the fact to help describe what I did rather than to describe what I was planning to do. I don’t do many sketches before hand – I am more likely to write down a list of the parameters, so I don’t forget anything along the way. If you ask me for “the plans”, generally these didn’t exist. I also don’t prepare a budget as that seems too much like work.

close up of No Duck Mo at 2018 Saskatoon show, closed

close up of No Duck Mo at 2018 Saskatoon show, open

linear view of No Duck Mo at 2018 Saskatoon show

To be continued...

Big Valley 2018

I first had the pleasure of attending “Big Valley” in August 2017. This is a Free-mo event hosted by the Calgary Free-mo group Calgary Free-mo. The event is held in an ice hockey arena in the village of Big Valley, Alberta located about an hour’s drive east of Red Deer. The collegial and welcoming organizers and participants include Free-mo modelers from the north-west United States and western Canada. While not advertised as being open to the public, it is and there is no admission charge to be a spectator. In 2017 there were over 540 linear feet of Free-mo modules.

As 2018 marked the 15th anniversary of Big Valley, the organizers set the ambitious goal of having at least 1,000 linear feet of modules – well in excess of the previous North America record of 599.75 feet which was set also at Big Valley in 2013, their 10th anniversary. This goal was exceeded, with 1,126 linear feet of modules comprising 1,900 feet of track on which to run trains over 135 modules. This took 1 Digitrax DCS240 command station, 26 track boosters and 12 accessory boosters to operate.

Having learned from the previous 14 years of Big Valley events, the organizers were superbly organized in the setup. They began the setup a day earlier than usual to ensure that adequate time was available. Setup began on the afternoon of Wednesday, August 15. Trains were running on Friday, August 17 and take-down began at 4 PM on Sunday, August 19. As with previous years, it was possible to run trains 24 hours a day if one was so inclined.

The organizers had also arranged for participants to engage in operating an actual locomotive and a couple of cars doing yard work in both the engineer and conductor roles. With safety training and proper clothing, we were supervised in these duties by employees of Alberta Prairie Railway.

If you are already a Free-mo modeler or are inclined to become one, this is an event not to be missed in a future year. Keep tabs on the Calgary Free-mo website for upcoming events.

Following are a few pictures from Big Valley 2018.

The following diagram is an image found on the Calgary Free-mo website. It is quite remarkable.

Big Valley 2017

Following are pictures from Calgary Free-mo’s Big Valley 2017 event held August 17 to 20. For more information, here is a link to their website Calgary Free-mo.

Big Valley, Alberta

ice hockey arena where the layout is set up


the set up day